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How to correctly install downlights and loft insulation

Here at Loft Leg, we get a number of questions from our customers on the topic of downlight installation in a ceiling, and how to correctly deal with the loft insulation above and around the fitting. If you’re wondering the same thing, this post is for you! Below, we’ll be dealing with installing downlights and the most popular method of insulating a loft; namely with quilt/mineral wool insulation. (If you’re looking at other forms of insulation, don’t panic! We’ll be going into those in future posts.)

Having a well-lit and energy-efficient home is a priority for many homeowners. However, when it comes to downlights and loft insulation, things can get a little tricky. Downlights need space around them to dissipate heat, while loft insulation needs to be continuous for maximum energy savings. So, how can you achieve both?

Firstly, it’s important to understand the type of downlight that is, or will be, installed. There are three main options - Halogen, LED and Integrated LED lamps - so we’ll examine each one in turn.

1. Halogen lamps and quilt/mineral wool insulation

Halogen downlights run at quite high temperatures, so it’s extremely important to ensure that they’re not covered directly with mineral wool insulation. Due to these high temperatures, halogen downlights require a volume of air around them to ensure that any heat generated is safely dissipated.

With that in mind, halogen bulbs can be covered with a fire retardant cap such as the Loft Lid, which will ensure there’s a safe volume of air around the lamp. Quilt insulation can then be rolled continuously over the cover, which creates the thermally insulating layer.

It’s worth remembering that Building Regulations (Part L Compliance - energy efficiency) states that insulation should not be compromised, without any reasonably avoidable gaps, and therefore needs to remain continuous to achieve the required thermal benefits.

A word of warning here - it’s extremely important that Dichroic bulbs are not installed in a ceiling, as these are designed specifically for display cabinets. While they look very similar, they can be very dangerous in this setting. If you are installing a downlight cover over an existing halogen bulb, it’s always a good idea to first check that it is not a Dichroic bulb. If it is, don’t risk it; just change the bulb.

2. LED bulb downlights and quilt/mineral wool insulation

LED bulbs run a lot cooler than halogen bulbs, which gives rise to the question: do you really need a cover for modern LED bulbs? In a nutshell: it depends! There are two types of standard LED downlights; fire rated and non-fire rated.

Fire-rated LEDs

Now, fire rated downlights don’t necessarily need a cover for heat or safety reasons, as these fittings have been designed so that quilt insulation can be installed directly over the top without causing any undue risk.

However, cutting holes in the ceiling for downlights creates air leakage. In effect, a heat chimney is created, which sucks hot air from the room below up into the loft. How it works is that basically, warm air rises, drawing the warm air from the room below up into the cold loft space, creating a form of chimney. The important thing is that it makes it more inefficient and expensive for you to heat your home.

Thankfully, there’s a solution! A downlight cover such as the Loft Lid, if sealed with a silicone sealant or mastic, creates an airtight seal around the fitting, maintaining the ceiling’s airtightness. This will ensure that no heat is unnecessarily lost through the fitting, into the loft.

Non fire-rated LEDs

As you’ve no doubt guessed, non-fire rated LED downlights cannot be covered by insulation directly. Building Regulations (Part L Compliance - energy efficiency) state that insulation should not be compromised, without any reasonably avoidable gaps, and should therefore remain continuous to achieve the required thermal benefits.

This means a cover must be fitted before quilt insulation is installed over the fitting. A fire retardant cover such as the Loft Lid will solve this problem.

Again, we should reiterate that cutting holes in the ceiling for downlights creates air leakage, so to avoid the same ‘heat chimney’ effect, we recommend using the Loft Lid downlight cover to create an effective airtight seal.

3. Integrated LED Downlights and quilt/mineral wool insulation

Due to the longevity of LED bulbs, many major manufacturers are moving towards ‘integrated LEDs’. Basically this means that the whole lamp fitting - not just the bulb - needs changing once the bulb has expired.

The manufacturers of most integrated LED fittings don’t recommend installing insulation directly over the fittings. Therefore a fire retardant cover is required, which will ensure that the fitting does not overheat.

The same applies for Integrated LEDs as it does for fire-rated and non fire-rated bulbs - once again, the fire retardant cover will need proper sealing, maintaining its air tightness to avoid the dreaded heat chimney effect.

How does Loft Lid solve the issues?

Essentially, one of the core functions of Loft Lid is to create a sealed physical barrier between the downlight itself and the surrounding thermal insulation, preventing direct contact between the two while providing the downlight with a reasonable amount of surrounding space. The Loft Lid can be used with Halogen or LED fittings, for both safety and energy efficiency.

How you can benefit from Loft Lid?

For halogen bulbs using Loft Lid over your downlights ensures that your fittings are safe and your home’s thermal efficiency is not compromised. It eliminates the dangers of any overheating due to contact between the downlights and the insulation, and it stops air leakage into the loft space, as well as the added benefits of preventing dust and insects dropping from the loft through to the room below!

For LED downlights the Loft Lid ensures the ceilings airtightness is maintained as well as preventing dust and insects dropping from the loft into the room below. They are particulary useful above LED downlights that are present over showers and bathrooms where a lot of moisture is present.

Perhaps most importantly, it ultimately ensures that you’re not spending more than you have to on heating your home, giving you peace of mind in knowing that your insulation is working at peak capacity. This is an especially tangible benefit in the chilly winter climates, where ineffective loft insulation could otherwise end up costing you a significant amount in wasted energy bills.

By following these steps, you can create a well-lit and energy-efficient home with both functional downlights and proper loft insulation. Remember, safety and efficiency go hand in hand!

Loft Lid can be used in conjunction with several other market-leading products we offer - including our namesake Loft Leg product - all of which can transform the way you use your loft space.

You can browse them right here on our site, or simply give us a call on 01282 861 001 if you have any questions or need any advice.

We’re here to help!

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